GPT-5.5 vs Grok 4.3

Choose GPT-5.5 if you want hard reasoning and coding for teams in the OpenAI ecosystem. Choose Grok 4.3 if you want frontier capability on a tighter budget.

In our editorial scoring, GPT-5.5 leads in 3 of five dimensions (output quality, agentic ability and reliability), while Grok 4.3 leads in 2. On price, GPT-5.5 runs about $13 per 1M tokens (blended) and is proprietary; Grok 4.3 is about $1.63 and proprietary.

The model is half the story — the agent is the other half

The model picks the moves; the agent runs the loop, the tools, and the guardrails. Once you've chosen a model, see which agent gets the most out of it.